Ignoring svn custom id lines on merge

Hello,

I'm starting tests to move from cvs to git, and i got just one
problem on all my tests.

We maintain a custom copy of FreeBSD sources, so, on
cvs we did follow when new FreeBSD version is released:

1. Import new freebsd src as a vendor branch
2. Merge changes on HEAD

I tried to do the same with git, and it worked, but since
almost all FreeBSD files has a custom Id like this:

$FreeBSD: release/7.0.0/COPYRIGHT 175036 2008-01-01 09:36:30Z imp $

These lines always change, because the place they stay
on svn repository (release/7.0.0, 7.1.0, 7.2.0) and git
generated a lot of conflicts to fix manually.

I would like to know if there is a way to configure git to
just ignore diffs on these lines and use the new one without
ask.

I can do it with diff command ignoring those lines, like this:

diff -q -I'[$]FreeBSD:.*$'

Thank you in advance
-- 
Renato Botelho